250w nominal does not mean anything, there is no limit on the maximum output. Yet.
It is not unthinkable the next e-bike limitation will be on maximum motor wattage instead of nominal.
That's funny I have always been of the understanding that the law already had the limit set at maximum wattage?
"European Union directive 2002/24/EC exempts vehicles with the following definition from type approval: "Cycles with pedal assistance which are equipped with an auxiliary electric motor having a
maximum continuous rated power of 0.25 kW, of which the output is progressively reduced and finally cut off as the vehicle reaches a speed of 25km/h (15.5mph) or if the cyclist stops pedaling." This is the de facto definition of an electrically assisted pedal cycle in the EU. As with all EU directives, individual member countries of the EU are left to implement the requirements in national legislation.
European product safety standard EN 15194 was published in 2009. The aim of EN 15194 is "to provide a standard for the assessment of electrically powered cycles of a type which are excluded from type approval by Directive 2002/24/EC"."
As an across the ponder that rides legal limit here bikes I don't have any skin in that game but just have always been curious how that works? I'm sure it is hashed out on here somewhere.
What sucks here is the Class I,II,III laws that are being enacted due to the influence of the manufactures and thier mouthpieces at the Bicycle Product Sales Association. We have existed just fine for years with the Federal and most states regs of 750w, doesn't specify nom or max, and speed limited to 20mph. All states can choose to either follow this or enact their own laws though they must adhere to the amendment to the Consumer Product Safety Commission known as HR 727.
"The text of HR 727 includes the statement: "This section shall supersede any State law or requirement with respect to low-speed electric bicycles to the extent that such State law or requirement is more stringent than the Federal law or requirements."
At speeds over 20mph bikes are subject to our Department of Transportation. Long list of shite to do there. Approved this, approved that, lights, horn, vin number, registration, far and above what the Speed Pedelec requirements over there are. So on the one end with the Class I pedelec only rating separating it from Class II for no other reason than it has a throttle is one thing. I know nobody likes throttles but in concert with a good TA and set to high torque/low speed they are very useful I find. I call it Class I.5. The Class II designation seems to allude to the fact that all anyone is going to do is ride the throttle exclusively. Which of course they can but they won't be going far as throttles are wh ogs and missing out on the best part of riding a bicycle. Pedaling it.
Class III clearly is non-compliant with HR 727 in that it is rated for 28mph putting it into the DOT zone.
Ebikes, while not as popular here as there, have been in use for just as long and the more generous wattage has led to all sorts of over volted bikes that haven't killed anyone yet to the best of my knowledge, and I've been hip to motor assist bikes for the last 18 yrs., but I am sure there has been plenty of road rash and broken bones. Some of the things I have seen are absolutely ridiculous but harmless in the fact that they wouldn't make it 50' on a trail system. Most of them stay on the road. There are exceptions for sure but so heavy and unwieldy that they wouldn't be much fun to ride. With the advent of access to dependable trail worthy legal wattage systems that do meet the regs it seems like those efforts are dwindling.
Good luck with your diy ebike build!
